Insurers fear escalating international tension could force aviation premiums still higher - and could lead to some airlines being grounded.
The warnings came as the government announced this week it was extending its insurance support on third-party war risk cover on UK airlines to the end of March.
However, it is saying it has no long-term underwriting role.
Aon director Jonathan Palmer-Brown, chairman of the aviation executive of the London Market Insurance Brokers' Committee, said: "Insurers will be looking at the Middle East issue. Higher premiums are a possibility. It's a natural effect of exposure."
He said: "If action took place it could give rise to seven-day notices, changing cover or charging higher premiums."
Insurers believe more continuity would be assured if the UK would agree to a global scheme backed by governments to handle aviation risk.
Marsh Aviation chairman Brian Moore said: "The ideal is that governments keep indemnifying."
He said the industry favoured the scheme proposed by the International Civil Aviation Organisation (ICAO), which involves the mutualisation of all states.
A Treasury spokesman said the 11-day cover extension was to allow time to hear the views of an EU transport committee meeting next week.
